Will you ____________ me English?[ ]
A. teach
B. taught
C. will teach
答案:A
已知数列{bn}的前n项和Sn满足bn=2﹣2Sn,则数列{bn}的通项公式bn=( )
※ [19~20]. ( 3 )
.
A. .
B. .
C. 2.
D. 2